The Power CMS Builder of Design Extender uses the Power CMS 2 files.
Upgrading the CMS Version of an older site will be a manual process.
The power CMS Files are located in your users configuration folder. for help finding the configuration folder, see the following page:
in the configuration folder, go to:
copy all of the folders in the CMS folder to your Sites CMS folder. you should delete the admin folder in your site to prevent confusion, the newer CMS uses the admin_cms folder.
If you installed CMS to a subfolder of your site initially, you wont be able to use Dreamweaver for managing the CMS Contents areas, you will need to continue using the developer notes and adding those to new pages as you had in the previous version.